Stratified Therapeutic Evaluation of Presbyphonia Based on Degree of Vocal Fold Atrophy: Efficacy and Prognostic Differences of Semi-Occluded Vocal Tract Training Across Different Stages.

Objective: This study aimed to evaluate the stratified therapeutic effects of semi-occluded vocal tract (SOVT) training based on the degree of vocal fold atrophy and to explore response trajectories. Methods: In this single-center prospective cohort study, 180 patients with presbyphonia were stratified into mild, moderate, and severe groups. All participants received standardized SOVT training and were followed for 8 weeks. The primary outcome was change in VHI-10. Secondary outcomes included GRBAS, maximum phonation time (MPT), cepstral peak prominence (CPP), acoustic perturbation parameters (jitter, shimmer, PPQ, APQ, and NHR), and glottal gap score. Linear mixed-effects models and latent class growth analysis (LCGA) were applied. Time effects referred to repeated measurements obtained at baseline, Week 4, and Week 8. Results: Significant overall improvements were observed in VHI-10, MPT, and CPP (all Conclusions: SOVT training is effective for presbyphonia, with therapeutic response varying according to the severity of vocal fold atrophy. Both cepstral and perturbation-based acoustic analyses supported progressive improvement after intervention. Patients with moderate vocal fold atrophy appeared to derive the greatest therapeutic benefit, suggesting a potential optimal therapeutic window for intervention. Stratified assessment and trajectory-based analysis may facilitate individualized voice rehabilitation strategies.