Awake transoral intralaryngeal botulinum toxin injection for early bilateral vocal fold immobility: a five-year...

To describe a single-centre clinical experience with awake intra-laryngeal botulinum toxin type A (BTXA) injection in adults with early-onset bilateral vocal fold immobility (BVFI), and to report temporal clinical observations associated with a staged bilateral injection protocol.

This retrospective observational study included 47 adult non-tracheostomized patients with early BVFI treated between January 2020 and March 2025. All patients underwent awake trans-oral BTXA injection under indirect laryngoscopic visualization (5 U per vocal fold). Bilateral treatment was performed using staged unilateral injections administered 24 h apart. Peak inspiratory flow (PIF) and Dyspnea Index (DI), voice and swallowing outcomes were assessed before injection and during follow-ups.

Improvement in airway-related measures was observed during follow-up. Median DI decreased after injection and median PIF increased during the expected pharmacological window of BTXA activity, with partial symptom recurrence by four months. Clinical improvement followed the known delayed pharmacodynamic profile of BTXA, with onset occurring after several days and peak effect within the first two weeks. Two patients required temporary tracheostomy and were subsequently decannulated. Voice and swallowing function remained largely preserved.

Awake intra-laryngeal BTXA injection was feasible as a reversible temporizing intervention for selected patients with early bilateral vocal fold immobility during the observation period. The staged bilateral injection strategy is presented as an experience-based technical approach that might help avoid tracheostomy in selected patients; however, a 24-hour interval between injections didn't appear to produce a clearly distinct staged pharmacodynamic effect. Findings should be interpreted as descriptive clinical observations requiring prospective validation.