The efficacy of botulinum toxin injection on adductor spasmodic dysphonia

Background: Adductor spasmodic dysphonia (ASD) is a voice disorder characterized by strained, stuttering-like voice (involuntary disruptions of voice). Botulinum toxin (BT) injection of the vocal folds (VFs) is the treatment of choice, however, the doses and method of injection are variable. Objectives: The aim of this study is to assess the effect of BT injection on the voices of the patients having ASD. Patients and Methods: Twelve patients with ASD treated bilaterally with VF BT injection in the office under local anesthesia. Each patient evaluated by laryngoscopic examination, acoustic analysis, and voice handicap index. Results: All patients improved markedly regarding laryngoscopic, acoustic, and self-assessment parameters. Conclusion: BT can be used effectively for the treatment of ASD and improving phonatory (voice) and quality of patients' life.