Posterior Cricoarytenoid Muscle Chemodenervation Can Improve Voice in Recalcitrant Dysphonia in Unilateral Vocal Fold Paresis With Synkinesis

Objectives: Patients with unilateral vocal fold paresis and unfavorable posterior cricoarytenoid (PCA) muscle synkinesis can be challenging to treat with medialization procedures alone. Arytenoid repositioning procedures are generally considered contraindicated in mobile vocal folds. We present two cases of persistent dysphonia following type I thyroplasty for vocal fold paresis that improved after botulinum toxin-A (BTX-A) injection into the PCA muscle. We aim to highlight the use and outcomes of BTX-A as an intervention for unfavorable PCA muscle synkinesis in unilateral vocal fold paresis.

Study design: Retrospective case series.

Methods: Two patients with long-standing unilateral left vocal fold hypomobility are described. Both patients underwent type 1 thyroplasty with partial improvement but with persistent posterior glottic insufficiency and dysphonia. BTX-A chemodenervation of the ipsilateral PCA muscle was performed to address residual respiratory glottal insufficiency. Injection was done percutaneously under electromyographic guidance with favorable voice improvement. Patient outcomes were based on laryngeal videostroboscopy, perceptual voice analysis, and patient-reported measures.

Results: Both patients achieved similar results following PCA muscle BTX-A injections. Their dysphonia was markedly improved within 2 weeks after injection, and their voice had nearly returned to nearly normal with adequate projection and endurance. Laryngeal videostroboscopy examinations showed an improved glottal closure pattern. Both patients experienced improvements in dysphonia.

Conclusion: BTX-A chemodenervation of the PCA muscle may be considered in the management of unilateral vocal fold paresis with residual posterior glottal insufficiency.