Using High-Speed Videoendoscopy to Analyze Laryngeal Closure Parameters During Normal Swallow.

Objective: This pilot study was designed to test the tolerability of a lower scope position and feasibility of custom-designed MATLAB graphical user interface (GUI) used to analyze playback review of laryngeal high-speed videoendoscopy (laryngeal HSV) during healthy volitional dry swallows. We hypothesized this method would conceptually provide time resolution for glottic closure events compared with standard (30 frames per second, fps), and enable a means to measure timing, sequence, and duration of laryngeal movements during swallowing not otherwise visualized.

Methods: A total of 14 healthy adults (4 male, 22-80 years) participated. We performed laryngeal HSV at 500fps. Measurements included: (i) feasibility and tolerability of the procedure; (ii) identification of a swallowing segment of interest (SOI) for the peak of the swallow; and (iii) description of laryngeal swallowing movements using a GUI.

Results: Fourteen subjects tolerated the procedure without discomfort and swallow images were able to be analyzed in 12. Using our GUI, mean SOI was 260 ms, yielding 130 frames for analysis (compared with seven in standard laryngoscopy). Vocal fold adduction, vocal fold medialization, and anterior-posterior arytenoid compression to the epiglottis prior to whiteout could be identified and sequenced.

Conclusion: Participants tolerated a low position of the endoscope during dry volitional swallows. The output of our GUI demonstrated a novel technique for identifying, describing, and sequencing a swallowing SOI. Future studies should investigate laryngeal closure and arytenoid positioning with a bolus and in a range of ages, genders, and etiologies in both healthy and abnormal populations to better understand swallowing physiology.

Level of evidence: NA Laryngoscope, 2024.