The Utility of Strap Muscle in Complex Type I Thyroplasties

Abstract

Introduction: Type I thyroplasty is a common procedure used to improve dysphonia secondary to glottic insufficiency caused by vocal fold paralysis, paresis, or bowing. Revision often involves more complex procedures that can be complicated by mucosal violation, hemorrhage, infection, and shifted or extruded implants. Intraoperative challenges can be managed successfully using autologous strap muscle rotation flaps.

Objectives: Review vocal fold medialization with strap muscle as a viable option for thyroplasty, particularly operations with inadvertent mucosal disruption.

Methods: All operative records of the senior author's 30-year experience were queried for modified, complex, or revision type I thyroplasties. Each of these was reviewed, and only those utilizing autologous strap muscle rotation flaps for vocal fold medialization were included. Changes in voice quality were assessed using strobovideolaryngoscopic assessment of glottic closure and Voice Handicap Index-10 (VHI-10) scores when available.

Results: Seven patients were found to have undergone eight type I thyroplasty using autologous strap muscle flaps. Improved glottic closure was seen in all patients except one. This patient, complicated by a laryngeal fracture of unknown origin discovered at the time of surgery, had worse voice with strap muscle implantation intraoperatively; therefore, the patient's fracture was reduced, and medialization was postponed. All other patients reported improved voice quality both intra- and postoperatively. Pre- and postoperative VHI-10 scores were available for two of the seven cases with successfully implanted strap muscles. A decrease in VHI-10 was observed in both cases (mean = 11). No postoperative complications occurred in any patient.

Conclusion: Although revision thyroplasties are relatively rare, they can be challenging. The seven cases presented herein illustrate the successful and safe use of autologous strap muscle rotation flaps for complex, revision type I thyroplasty procedures. They are particularly helpful in cases requiring additional soft tissue between the thyroid cartilage and mucosa in preparation for possible future medialization after Gore-Tex or Silastic implants, and for inadvertent mucosal disruption in which using a foreign implant might pose a risk of infection. Future studies should be performed with larger populations and longer follow-up to confirm the efficacy and safety of this procedure.

Keywords: Complex; Flap; Laryngoplasty; Modified; Muscle; Revision; Type I thyroplasty.