Improved Voluntary Cough Strength and Swallowing Safety Following Office-Based Injection Laryngoplasty

Objective: This study aimed to investigate the following hypotheses in patients undergoing injection laryngoplasty (IL): (1) glottic insufficiency affects voluntary cough airflow dynamics, (2) restoring glottic competence improves cough strength, and (3) a readily accessible tool can be utilized for quantifying cough strength, which facilitates the measurement of changes pre- and post-injection, as well as subsequent expiratory muscle strength training and swallowing training.
Methods/Design: A prospective study was conducted on subjects with glottic insufficiency due to unilateral vocal fold paresis or paralysis. Instrumental assessments included voluntary cough airflow measurements by a breathing strength builder (BravoTM Trainer, GaleMed Corporation, Taiwan), general conversation recordings, and completion of the VHI-10 and EAT-10 questionnaires (filled by those complaining of choking). Wilcoxon signed-rank test was used for numerical comparisons before and after IL.
Results: Forty-one patients (15F:26M, mean age 58.7) participated in airflow measurements; 19 patients reported choking issues before the study. Post-IL, there was a significant increase in maximum cough pressure, indicating improved coughing effectiveness. Sixteen patients reported substantial improvement in choking after IL.
Conclusions: This study suggests that IL enhances cough effectiveness in patients with glottic insufficiency and may contribute to preventing aspiration and penetration. The results indicate that improvements in cough airflow measurements can be tracked through changes in maximum cough pressure, providing valuable clinical insights.