  Upper esophageal sphincter is an important anatomical landmark of the
swallowing process commonly observed through the kinematic analysis of
radiographic examinations that are vulnerable to subjectivity and clinical
feasibility issues. Acting as the doorway of esophagus, upper esophageal
sphincter allows the transition of ingested materials from pharyngeal into
esophageal stages of swallowing and a reduced duration of opening can lead to
penetration/aspiration and/or pharyngeal residue. Therefore, in this study we
consider a non-invasive high resolution cervical auscultation-based screening
tool to approximate the human ratings of upper esophageal sphincter opening and
closure. Swallows were collected from 116 patients and a deep neural network
was trained to produce a mask that demarcates the duration of upper esophageal
sphincter opening. The proposed method achieved more than 90\% accuracy and
similar values of sensitivity and specificity when compared to human ratings
even when tested over swallows from an independent clinical experiment.
Moreover, the predicted opening and closure moments surprisingly fell within an
inter-human comparable error of their human rated counterparts which
demonstrates the clinical significance of high resolution cervical auscultation
in replacing ionizing radiation-based evaluation of swallowing kinematics.
