Article

The purpose of this study was to (1) depict normal dynamic swallowing and (2)
measure (a) the temporal characteristics of three components of laryngeal
closure, i.e., true vocal cord (TVC) closure, closure of the laryngeal vestibule
at the arytenoid to epiglottic base, and epiglottic inversion, and (b) the
temporal relationship between these levels of laryngeal closure and other
swallowing events, hyoid elevation, and the pharyngoesophageal segment (PES)
using 320-detector-row multislice computed tomography (320-MSCT). The swallowing
of a 10-ml portion of honey-thick liquid (5% w/v) was examined in six healthy
volunteers placed in a 45 degrees reclining position. Three-dimensional CT images
were created in 29 phases at an interval of 0.10 s over a 2.90-s duration.
Dynamic swallowing and TVC movement were depicted clearly. The sequence for
laryngeal closure was the following: (1) the hyoid started to elevate, (2) the
PES opened, (3) TVC closure and closure at the arytenoid to epiglottic base
occurred almost simultaneously during the hyoid elevation, and (4) the epiglottic
maximum inversion occurred after the hyoid maximum displacement. Those results
indicated that the onset of hyoid elevation and the early opening of the PES
occurring before three levels of laryngeal closure are critical components for
airway protection. 320-MSCT allowed the 3D depiction and kinematic analysis of
target structures, which will increase our knowledge of airway protection
mechanisms during swallowing.

Langue : ANGLAIS