Figure 2.

Endoscopic assessment of upper airway structure and function. (A) Modified sialendoscope with micromanipulator control for precise transoral insertion. Representative endoscopic images of a mouse pharynx (B) and larynx (C) with labeled structures. In mice, the glottal edge is formed predominantly by the arytenoids (black asterisks); the proportionately smaller vocal folds (red arrows) are nearly obscured by the epiglottis (yellow asterisk); red dots indicate the location of the arytenoid vocal process. (D) Air pulse stimulation of the arytenoid mucosa near the dorsal commissure evokes the glottic closure reflex (i.e., laryngeal adductor reflex, LAR), identified by brief, bilateral medialization of the arytenoids and vocal folds. (E) Tracking lines positioned along the left (blue) and right (red) glottal edge using our VFTrack™ software, based on the location of three manually placed markers within the software interface: blue (left arytenoid vocal process), red (right arytenoid vocal process), and green (dorsal commissure). (F) Representative plot showing automated tracking of glottal edge open/close motion during spontaneous breathing under light sedation. Green and red dots indicate when the glottis is maximally opened during inspiration vs. maximally closed during expiration, respectively.