Supraglottic Botulinum Toxin Injection Improves Symptoms of Laryngeal Sensory Dysfunction.

Abstract

Central/peripheral vagal hypersensitivity underpins laryngeal sensory dysfunction (LSD). Botulinum toxin type A (BoNT-A) injection has emerged as a targeted treatment for modulating laryngeal sensory pathways. This study aimed to evaluate short-term outcomes and predictors of response following supraglottic BoNT-A injection in patients with refractory LSD. Retrospective cohort study of patients undergoing supraglottic BoNT-A injection treatment between 2019 and 2025 for LSD symptoms refractory to medical/behavioral therapy. Outcome measures included the Newcastle Laryngeal Hypersensitivity Questionnaire (LHQ), Reflux Symptom Index (RSI), Cough Severity Index (CSI), and Voice Handicap Index-10 (VHI-10). Pre- and post-treatment scores were compared using paired statistical tests and effect size estimation. Treatment characteristics and follow-up duration were reported, along with attainment of minimal clinically important difference (MCID) and predictors of response. Eighty consecutive patients (mean age 58.3 years; 48 female) showed significant improvement across hypersensitivity domains: LHQ +3.1 (95% CI: 2.4-3.8, p < 0.001), RSI -7.9 points (95% CI: -9.7 to -5.8, p < 0.001), CSI -5.7 points (p < 0.001). VHI-10 was unchanged (-1.3, p = 0.20). MCID thresholds were achieved in 64% for LHQ and 56% for RSI. Overall, 71% of patients reported phenotypic and clinically relevant improvement. Patients with a positive short-term superior laryngeal nerve (SLN) block were more likely to respond to supraglottic BoNT. No serious complications occurred. Supraglottic BoNT-A injection is a safe, effective treatment for laryngeal sensory dysfunction targeting the sensory field of the SLN to provide clinically meaningful reductions in throat irritation without compromising voice function.