Minithyrotomy with radiofrequency-induced thermotherapy for the treatment of adductor spasmodic dysphonia.
A simple, safe and effective surgical alternative for treating adductor spasmodic dysphonia (ADSD) would appeal to many patients. This study evaluates a new option, using radiofrequency-induced thermotherapy (RFITT) of the thyroarytenoid muscle (TA) via the minithyrotomy approach to reduce the force of adduction.



Fifteen dogs were used. In part 1, the optimal RFITT power settings, exposure time, probe location, and number of passes were determined. Part 2 compared laryngeal adductor pressures (LAPs) at baseline; immediately postintervention; and at 1, 3, or 6 months postintervention. Interventions included RFITT via the transcervical minithyrotomy approach (n = 15), transoral RFITT (n = 3), botulinum toxin (Botox) injection (n = 3), or no-intervention controls (n = 3). Postintervention induced phonation and histologic analyses were performed as well.



In the minithyrotomy RFITT group, the mean LAP was 30.3% of baseline immediately posttreatment. At 1, 3, and 6 months postoperatively, the mean LAPs were 24.9%, 44.8%, and 43.5%, respectively. Transoral RFITT reduced LAP to 56.6% of baseline immediately posttreatment, but returned to normal in the 1 and 3 month animals. The Botox injections dropped the LAP to 57% of baseline at 1 month, but returned to normal at 3 months. Mucosal waves, based on induced phonation stroboscopy, were present at the terminal date in all animals. Thirteen of 15 transcervical RFITT preparations (87%) showed no injury to the lamina propria, whereas 80% showed evidence of TA muscle atrophy and fibrosis.



Minithyrotomy RFITT is a feasible technique that shows encouraging long-term results for the potential treatment of patients with ADSD.



N/A. Laryngoscope, 126:2325-2329, 2016.
Department of Otolaryngology-Head and Neck Surgery, Washington University School of Medicine, St. Louis, Missouri.
Shaun C
SC
Desai
Department of Otolaryngology-Head and Neck Surgery, Washington University School of Medicine, St. Louis, Missouri.
Andrea M
AM
Park
Department of Pathology, Washington University School of Medicine, St. Louis, Missouri.
Rebecca D
RD
Chernock
Department of Otolaryngology-Head and Neck Surgery, Washington University School of Medicine, St. Louis, Missouri. paniellor@ent.wustl.edu.
Randal C
RC
Paniello
D000818:Animals; D003131:Combined Modality Therapy; D003972:Diathermy / Q000379:methods*; D004195:Disease Models, Animal; D004285:Dogs; D055154:Dysphonia / Q000503:physiopathology / Q000628:therapy*; D005240:Feasibility Studies; D007821:Laryngeal Muscles / Q000503:physiopathology / Q000601:surgery; D013517:Otorhinolaryngologic Surgical Procedures / Q000379:methods*; D010699:Phonation; D049489:Stroboscopy; D016896:Treatment Outcome
Spasmodic dysphonia; radiofrequency; surgery