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Myoneurectomy for Adductor Spasmodic Dysphonia: Long-Term Outcomes, Complications, and Recurrence
Domingos Hiroshi Tsuji1, Adriana Hachiya2, Rui Imamura1
1Department of Otorhinolaryngology, University of Sao Paulo School of Medicine, Sao Paulo, Brazil.
Objective:
To evaluate the long-term results of endoscopic myoneurectomy (EMN) of the thyroarytenoid (TA) muscle for the treatment of adductor spasmodic dysphonia (AdSD), with an emphasis on vocal outcomes, adverse effects, and recurrence.
Methods:
A total of 48 patients underwent up to three EMNs of the TA muscle and were followed for at least 18 months to evaluate the efficacy, based on patient and examiner assessments, and safety of the procedure(s). Vocal outcomes were evaluated through the use of the 30-item Voice Handicap Index (VHI-30) questionnaire and subjective (patient-reported) assessment.
Results:
In this group, 38 patients (79.2%) were considered successful. The median VHI-30 score at baseline was 97, decreasing to 26 after treatment, and the median subjective postprocedural improvement was 88.5%. The most common adverse effects were granulomas (in 18 cases), glottic insufficiency (in two), and dyspnea (in one).
Conclusions:
Although up to three procedures can be needed to achieve a high success rate, EMN of the TA muscle can provide excellent benefits in terms of vocal function with a low rate of complications.
Level Of Evidence:
4 Laryngoscope, 135:1444-1450, 2025.
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