[Multidimensional modulation of anterior glottoplasty and its effects on voice function: an experimental study]

Objective: To evaluate the effects of different surgical parameters of anterior glottoplasty, including the extent of vocal fold shortening, suture depth, and subglottic suture range, on voice function using an ex vivo canine larynx model. Methods: From October 2025 to February 2026, ex vivo larynges from 20 adult male Chinese rural dogs (aged 2-3 years, weighing 20-30 kg) were used to establish experimental models with varying degrees of vocal fold shortening (0-50%), different horizontal suture depths (mucosal layer, vocal ligament layer, and vocalis muscle layer), and varying subglottic suture ranges (vocal fold, subglottis, and perichondrium of thyroid cartilage). The fundamental frequency (F₀), sound pressure level (SPL), phonation threshold pressure (PTP), phonation threshold flow (PTF), and phonation threshold power (PTW) were measured and compared across groups. Statistical analysis was performed using SPSS 27.0 software. Results: With increasing extent of vocal fold shortening, F₀ increased significantly (from 233.0±35.81 Hz to 378.30±44.69 Hz, F=83.68, P<0.05), accompanied by increases in PTP, PTF, and PTW, while, SPL decreased (all P<0.05). Different horizontal suture depths had no significant effect on any parameter (all P>0.05). When the subglottic suture range was extended to the thyroid cartilage perichondrium, F₀ was significantly elevated compared with both the vocal fold suture group and the subglottic suture group (from 259.6±43.47 Hz to 329.20±30.61 Hz, F=5.12,P<0.05), while, no significant differences were observed in SPL, PTP, PTF, or PTW (all P>0.05). Conclusion: The extent of vocal fold shortening is the core surgical parameter for elevating F₀. A membranous vocal fold shortening of 30%-40% in the canine larynx model achieves a balance between pitch elevation and phonatory efficiency. Increasing suture depth alone yields limited benefits for F₀ elevation, whereas extending subglottic mucosal sutures to the thyroid cartilage perichondrium can significantly increase F0 without imposing additional aerodynamic burden, suggesting its potential value for surgical optimization.