Fig. 4.

Infusion of green-colored water into the hypopharynx at 1 mL/ min in an elderly subject. (A) Onset of water perfusion (timer at 00:51: 24.77). (B) Colored water seen accumulating in the hypopharynx. (C) With ongoing perfusion, the colored water was seen rising up to the superior margin of the interarytenoid fold. (D) Further perfusion did not elicit reflexive pharyngeal swallow, which led to water spilling into the larynx. (E) To prevent aspiration, the subject was asked to swallow (command swallow). [Color figure can be viewed in the online issue, which is available at wileyonlinelibrary.com.]